Specifications

Cinterion
®
ALAS66A Hardware Interface Overview
2.2 GSM/UMTS/LTE Antenna Interface
33
 ALAS66A_HIO_v01.000 2018-12-11
Confidential / Preliminary
Page 24 of 50
2.2 GSM/UMTS/LTE Antenna Interface
The ALAS66A GSM/UMTS/LTE antenna interface comprises two GSM/UMTS/LTE main an-
tennas as well as two UMTS/LTE Rx diversity/MIMO antennas to improve signal reliability and
quality
1
. The interface has an impedance of 50. ALAS66A is capable of sustaining a total mis-
match at the antenna interface without any damage, even when transmitting at maximum RF
power.
The external antennas must be matched properly to achieve best performance regarding radi-
ated power, modulation accuracy and harmonic suppression. Matching networks are not in-
cluded on the ALAS66A PCB and should be placed in the host application, if the antenna does
not have an impedance of 50
.
Regarding the return loss ALAS66A provides the following values in the active band:
1. By delivery default the UMTS/LTE Rx diversity/MIMO antennas are configured as available for the mod-
ule since its usage is mandatory for LTE. Please refer to [1] for details on how to configure antenna set-
tings.
Table 4: Return loss in the active band
State of module Return loss of module Recommended return loss of application
Receive >
8dB > 12dB
Transmit Undefined mismatch >
12dB